# std::islower(std::locale)

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< cpp‎ | locale

Defined in header `<locale>` |  |
template< class CharT > bool islower( CharT ch, const locale& loc ); |  |

Checks if the given character is classified as a lowercase alphabetic character by the given locale's std::ctype facet.

### Parameters

ch | - | character
loc | - | locale

### Return value

Returns true if the character is classified as lowercase, false otherwise.

### Possible implementation

    template<class CharT>
    bool islower(CharT ch, const std::locale& loc)
    {
        return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::lower, ch);
    }

### Example

Demonstrates the use of `islower()` with different locales (OS-specific).

Run this code

    #include <iostream>
    #include <locale>

    int main()
    {
        const wchar_t c = L'\u03c0'; // GREEK SMALL LETTER PI

        std::locale loc1("C");
        std::cout << std::boolalpha
                  << "islower('π', C locale) returned "
                  << std::islower(c, loc1) << '\n'
                  << "isupper('π', C locale) returned "
                  << std::isupper(c, loc1) << '\n';

        std::locale loc2("en_US.UTF8");
        std::cout << "islower('π', Unicode locale) returned "
                  << std::islower(c, loc2) << '\n'
                  << "isupper('π', Unicode locale) returned "
                  << std::isupper(c, loc2) << '\n';
    }

Possible output:

    islower('π', C locale) returned false
    isupper('π', C locale) returned false
    islower('π', Unicode locale) returned true
    isupper('π', Unicode locale) returned false

### See also

islower | checks if a character is lowercase (function)
iswlower | checks if a wide character is lowercase (function)

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